by Naomi White, Science Teacher, Jefferson High School, LAUSD

Investigation Question:
How does Los Angeles River water compare to tap water and distilled water in pH, amount of chlorine, copper, iron, and water hardness?

Hypothesis:
Chlorine should be present in tapwater due to its addition during water treatment. River water should be harder than tapwater and contain more copper and iron due to water treatment. Distilled water should show little/no chlorine, iron, copper, and would be soft.

Experimental Design:

Independent variable: pH measurement, water hardness and amounts of copper, iron, chlorine present in samples of tap water, river water, and distilled water.

Dependent variable: source of water and water treatment

Controlled Variable: collected same day; same sample size; same procedures and observation method

Materials:

Pond/River Water Tour - LaMotte / price: $46.95/call: 1-888-222-1332/kit#: F23840

Instructions: e-mail data to target@lalc.k12.ca.us

Time of Day:
Location along river:
Where water samples were collected:
Location of tap water:

	pH	chlorine ppm	copper ppm	iron ppm	water hardness ppm
Distilled water
L.A. River water
L.A. tapwater
______ Other
______ Other

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Los Angeles River Connection is a part of LAEP Learning Exchange.
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